In a statement on Monday, Saudi Arabia said the Senate's resolution "contained blatant interferences" in the kingdom's internal affairs and undermined its regional and international role.

The resolution was based on "unsubstantiated claims and allegations," the statement also said.

"The kingdom categorically rejects any interference in its internal affairs, any and all accusations, in any manner, that disrespect its leadership ... and any attempts to undermine its sovereignty or diminish its stature," it said.

The statement was also tempered in saying the kingdom "reaffirms" its commitment to relations with the US and describing the Senate as "an esteemed legislative body of an allied and friendly government."

Relations between the US and Saudi Arabia have taken a hit over the killing. Credit: AP

Donald Trump has been reluctant to condemn the crown prince, despite intelligence officials concluding that Prince Mohammed must have at least had knowledge of the plot.

President Trump instead has touted Saudi arms deals worth billions of dollars and has thanked the Saudis for lower oil prices.

Saudi Arabia said its investigations concluded that the crown prince's aides had plotted to bring Mr Khashoggi by force back to Saudi Arabia and that the agents on the ground exceeded their authority and killed him.

Strong rebukes from the Saudisare usually reserved for those who criticise the kingdom's human rights record, such as Sweden in 2015 after the public flogging of a blogger, and Canada this year over the arrests of women's rights activists.